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Risk assessment and environmental influencing factors of urinary polycyclic aromatic hydrocarbons metabolites in pregnant women in Zunyi,China
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作者 Jing Yang Jing Jiang +9 位作者 Linfei Wu Pei Xu Nian Wu Rui Yu Yanling Xiao Xingting Zheng Rong Zeng Yuanzhong Zhou Yan Xie Xubo Shen 《Journal of Environmental Sciences》 2026年第1期617-623,共7页
Despite the widespread presence and frequent detection of polycyclic aromatic hydrocarbons(PAHs)in various aspects of life,there is limited research on their exposure levels in pregnant women and cumulative exposure f... Despite the widespread presence and frequent detection of polycyclic aromatic hydrocarbons(PAHs)in various aspects of life,there is limited research on their exposure levels in pregnant women and cumulative exposure from the living environment.This study included 1311 women in late pregnancy from the Zunyi birth cohort and measured the urinary concentrations of 10 hydroxylated PAH metabolites(OH-PAHs).Risk assessment was conducted based on the estimated daily intake to calculate the hazard quotient and hazard index(HI).A linear regression model was used to analyze the relationship between creatinine-adjusted OH-PAHs concentrations and living environment and lifestyle factors,while principal component analysis was applied to trace the sources of PAHs exposure.1-OHPYR was detected in all participants’urine,with naphthalene metabolites having the highest concentrations among creatinine-adjusted PAHs.OH-PAHs concentrations were associated with housing type,room number,cooking frequency,household size,exercise frequency,fuel type,distance from main road,and drinking water source.Pregnant women using traditional fuels and living in bungalows had higher health risks than those using clean energy and living in buildings.Those living within 100 m of a main road had higher HI than those farther away.Coal combustion was identified as the primary source of PAHs exposure.The study emphasizes the importance of reducing PAHs exposure,especially for pregnant women living in polluted environments.It recommends public health interventions such as improving indoor ventilation and providing clean energy to reduce related health risks. 展开更多
关键词 Polycyclic aromatic hydrocarbons Pregnant women environmental factor Daily intake estimation Risk assessment
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GeoChip-Based Microbial Functions in Biogeochemical Cycles and Their Responses to Environmental Factors in Tengchong Hot Springs
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作者 Muhammad Inayat Ullah Khan Liuqin Huang +3 位作者 Geng Wu Jian Yang Xiangyu Guan Hongchen Jiang 《Journal of Earth Science》 2025年第2期382-394,共13页
Microorganisms actively participate in biogeochemical cycling processes and play a crucial role in maintaining the dynamic balance of hot spring ecosystems.However,the distribution of microbial functional genes and th... Microorganisms actively participate in biogeochemical cycling processes and play a crucial role in maintaining the dynamic balance of hot spring ecosystems.However,the distribution of microbial functional genes and their influencing factors in hot springs remain largely unclear.Therefore,this study investigated the microbial functional genes and their potential for controlling biogeochemical cycles(C,N,S,and P) in the hot Springs of Tengchong,China,using the Geochip method,a functional gene microarray technology.The examined hot springs have very different microbial functional genes.A total of 22 736 gene probe signals were identified,belonging to 567 functional genes and associated with 15 ecological functions,mainly involving stress response,carbon cycle,nitrogen cycle,sulfur cycle,phosphorus cycle and energy processes.The amyA,narG,dsrA and ppx genes were most abundant in carbon,nitrogen,sulfur and phosphorus cycles,respectively,and were significantly correlated with pH,temperature and SO_(4)^(2-).The diversity and abundance of detected gene probes were negatively correlated with temperature.The α-diversity(i.e.,Shannon index) was high at low temperature and low pH.Molecular functional interactions revealed by the gene connectivity levels were negatively correlated with temperature,pH and SO_(4)^(2-).These results suggested that the abundance,diversity and interactions of microbial functional genes were significantly influenced by geochemical parameters.-In addition,some genera possessed functional genes related to carbon,nitrogen,sulfur,and phosphorus cycles and can synergistically control the biogeochemical cycles of carbon,nitrogen,sulfur and phosphorus.These findings provide new insights into the functional potentials of microorganisms to participate in biogeochemical cycles and their responses to environmental factors in hot springs. 展开更多
关键词 GeoChip functional genes biogeochemical cycles environmental factors microbial community GEOBIOLOGY environment geology
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Expeditionplus:The application of a gridded system in the integration of multidimensional environmental factors
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作者 Xinyuan Kuai Quansheng Fu +1 位作者 Hang Sun Tao Deng 《Plant Diversity》 2025年第4期702-708,共7页
The study of plant diversity is often hindered by the challenge of integrating data from different sources and different data types.A standardized data system would facilitate detailed exploration of plant distributio... The study of plant diversity is often hindered by the challenge of integrating data from different sources and different data types.A standardized data system would facilitate detailed exploration of plant distribution patterns and dynamics for botanists,ecologists,conservation biologists,and biogeographers.This study proposes a gridded vector data integration method,combining grid-based techniques with vectorization to integrate diverse data types from multiple sources into grids of the same scale.Here we demonstrate the methodology by creating a comprehensive 1°×1°database of western China that includes plant distribution information and environmental factor data.This approach addresses the need for a standardized data system to facilitate exploration of plant distribution patterns and dynamic changes in the region. 展开更多
关键词 Gridded system Data integration Multidimensional environmental factors Western China GIS Plant distribution
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Socioeconomic and Environmental Factors Influence Tuberculosis Control
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作者 Lei Gao 《Biomedical and Environmental Sciences》 2025年第7期779-780,共2页
As a major global public health issue,tuberculosis is closely related to multiple socio-ecological factors in its epidemiological patterns~([1]).China,as a high-burden country for tuberculosis,exhibits regional variat... As a major global public health issue,tuberculosis is closely related to multiple socio-ecological factors in its epidemiological patterns~([1]).China,as a high-burden country for tuberculosis,exhibits regional variations in the distribution of the tuberculosis epidemic.To enhance the efficiency of prevention and control,its strategies are undergoing a transition toward regionally differentiated approaches~([2]). 展开更多
关键词 prevention control strategies public health socioeconomic factors tuberculosis control regional variations environmental factors regionally differentiated approaches
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Spatiotemporal distribution patterns of macrobenthic communities and their relationship with environmental factors in the Shengsi Archipelago(Zhejiang,China)
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作者 Lingxiang Jin Yibo Liao +6 位作者 Peisong Yu Yanbin Tang Qinghe Liu Rongliang Zhang Lu Shou Jiangning Zeng Quanzhen Chen 《Acta Oceanologica Sinica》 2025年第1期113-126,I0001-I0011,共25页
Macrobenthic organisms are commonly employed as biomonitors for environmental risk assessment.In this study,we aimed to investigate the spatial and temporal patterns of the macrobenthic community,which is influenced b... Macrobenthic organisms are commonly employed as biomonitors for environmental risk assessment.In this study,we aimed to investigate the spatial and temporal patterns of the macrobenthic community,which is influenced by environmental factors of sediments and bottom water layer.We sampled a total of 12,11,10,and 11 stations in the Shengsi Archipelago during June 2010,August 2010,November 2020,and April 2021 respectively.A total of 124 species of macrobenthos were identified,with polychaetes being the dominant group.The abundance,biomass,and diversity indices exhibited no significant temporal differences.Similarly,biodiversity did not exhibit a clear spatial gradient,likely due to the small study area and the absence of significant differences in key factors such as depth.However,the stations with the lowest biodiversity values consistently appeared in the southwest region,possibly due to the impact of human activities.Significant differences in the macrobenthic community were observed between all months except between June and August,and mollusk Endopleura lubrica and polychaete Sigambra hanaokai were important contributors to these differences according to the results of the Similarity Percentages analysis.Suspended particulate matter(SPM)was identified as the primary driving factors of macrobenthic variability.In summary,the community structure underwent temporal changes influenced by complex current patterns,while biodiversity remained relatively stable.This study contributes to our understanding of the key environmental factors affecting macrobenthic communities and biodiversity.It also provides valuable data support for the long-term monitoring of macrobenthos and the environment in the Shengsi Archipelago. 展开更多
关键词 macrobenthic community Shengsi Archipelago distribution pattern BIODIVERSITY environmental factors
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Roles of genetic and environmental factors in psychiatric comorbidities among children with neurodevelopmental delays
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作者 Lin Li Li-Juan Song +1 位作者 Xiao-Li Liu Zhen-Fang Wang 《World Journal of Psychiatry》 2025年第10期155-164,共10页
BACKGROUND Neurodevelopmental delays encompass a wide range of conditions that impair cognitive,motor,and social functioning,often increasing the risk of psychiatric comorbidities.Children with these delays frequently... BACKGROUND Neurodevelopmental delays encompass a wide range of conditions that impair cognitive,motor,and social functioning,often increasing the risk of psychiatric comorbidities.Children with these delays frequently present with disorders such as attention-deficit/hyperactivity disorder(ADHD),anxiety,and behavioral disturbances,which can significantly affect development and quality of life.While genetic predisposition has been linked to these comorbidities,growing evidence highlights the role of environmental factors,including prenatal and early-life stressors.However,the interaction between genetic susceptibility and environmental influences remains poorly understood.Identifying specific genetic variants,environmental risks,and their interactions is essential for early detection and targeted interventions.AIM To investigate the combined effects of genetic and environmental factors on psychiatric comorbidities in children with neurodevelopmental delays,elucidate underlying mechanisms,and inform clinical management strategies.METHODS This retrospective cohort study included 80 children with confirmed neurodevelopmental delays and 40 age-and sex-matched typically developing controls.Comprehensive clinical and psychiatric evaluations,genetic testing(chromosomal microarray analysis and targeted next-generation sequencing),and environmental exposure assessments were conducted.Statistical analyses explored associations between genetic variants and psychiatric comorbidities,environmental risk factors,and gene-environment interactions.RESULTS Children with neurodevelopmental delays exhibited significantly higher rates of psychiatric comorbidities(70.0%)compared to controls(15.0%),with ADHD(42.5%),anxiety disorders(28.8%),and behavioral disorders(23.8%)being the most common.Pathogenic genetic variants were identified in specific pathways associated with distinct psychiatric presentations:Glutamatergic signaling variants were linked to anxiety disorders(odds ratio=3.8),dopaminergic system variants to ADHD(odds ratio=4.2),and synaptic function variants to both behavioral and anxiety disorders.Environmental factors,particularly prenatal maternal stress,early childhood adversity,and family dysfunction were strong predictors of psychiatric outcomes(β=0.42).Significant gene-environment interactions were identified,indicating that environmental exposure can moderate the effects of genetic risks on psychiatric outcomes.CONCLUSION Psychiatric comorbidities in children with neurodevelopmental delays are significantly influenced by both genetic and environmental factors,with complex interactions between the two.These findings underscore the need for integrated assessments and targeted interventions addressing both biological and environmental contributors to improve outcomes in this vulnerable population. 展开更多
关键词 Neurodevelopmental delay Psychiatric comorbidity Genetic factors environmental factors Child development
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Connection methods in landslide susceptibility assessment:Suitability evaluation based on environmental factor type
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作者 JIA Yifan YANG Hongjuan +1 位作者 ZHANG Shaojie WANG Xiuying 《Journal of Mountain Science》 2025年第8期2996-3016,共21页
Connection methods are essential for integrating environmental factors with machine learning models for landslide susceptibility assessments.However,current research does not consider the different characteristics of ... Connection methods are essential for integrating environmental factors with machine learning models for landslide susceptibility assessments.However,current research does not consider the different characteristics of continuity and discreteness within environmental factors and therefore does not analyze the suitability of various connection methods for different factor types.Moreover,the applicability of connection methods remains unclear when slope units are used as the basic assessment units.This study employed slope units as mapping units.The original data of 15 environmental factors,including 12 continuous and three discrete factors,and two connection methods,i.e.,frequency ratio(FR)and modified FR(MFR),were separately used to construct the input datasets for landslide susceptibility modeling.The performance of four widely used machine learning models,random forest(RF),support vector machine(SVM),logistic regression(LR),and multilayer perceptron(MLP),was analyzed to evaluate the suitability of the connection methods for landslide susceptibility mapping.The results show that,in contrast to the decision tree-based RF model,the use of different connection methods for different factor types significantly influences the results of nontree models,including SVM,MLP,and LR.SVM model is the most sensitive to factor types and connection methods.When the MFR is used as the connection method,it improves the mapping results,especially for the SVM model.This shows that it is essential to consider the different characteristics of the data and select an appropriate environmental factor connection strategy to increase the effectiveness of landslide susceptibility evaluation.Furthermore,this study explored the role of connective methods from a sample distribution perspective,providing a theoretical foundation for the more rational and effective integration of environmental factors. 展开更多
关键词 Landslide susceptibility mapping environmental factor integration Slope unit Machine learning model Modified frequency ratio Model sensitivity
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Environmental Factors and Their Relationship with Nitrogen Compounds in Walnut Tree(Carya illinoinensis)
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作者 JoséNicolás García-Ramírez Dalia Ivette Carrillo-Moreno +4 位作者 Luis Manuel Valenzuela-Núñez Viridiana Contreras-Villareal Rubén López-Salazar Edwin Amir Briceño-Contreras Fernando Arellano Rodríguez 《Research in Ecology》 2025年第4期203-213,共11页
Total Soluble Proteins(TSP)and Total Amino Acids(TAA)help to tolerate adverse conditions in fruit trees.The objective of this research was to determine the influence of temperature and irradiation on the concentration... Total Soluble Proteins(TSP)and Total Amino Acids(TAA)help to tolerate adverse conditions in fruit trees.The objective of this research was to determine the influence of temperature and irradiation on the concentration of TSP and TAA in Carya illinoinensis trees.Pearson’s correlation and multiple regression were made using mean temperature(℃)and irradiation(MJ·m^(2))data.The concentration of the TSP related to the temperature and irradiation in root,two correlation models were obtained,one for WN cultivar(F=3.969,df=2.9,P>0.058,R2=0.469)and another one for the WA cultivar(F=1.559,df=2.9,P>0.145,R=0.507)where it was observed that the varieties have the same behavior in root for TSP.However,in the stem,the WA cultivar(R=7.31,gl=2.9,P<0.013,R=0.788)presented a greater mobility of TSP.In the case of WN cultivar,a lower mobility of TSP was observed(F=2.407,gl=2.9,P>0.145,R=5.90).In TAA,significant differences were observed in both cultivars:in WN cultivar,the correlation model was observed thatat lower temperature and irradiation(F=12.988,gl=2.9,P<0.002,R=0.862),the concentration of TAA increases.InWA cultivar,it was found(F=17.481,gl=2.9,P<0.01,R=0.892)that lower temperature and irradiation decrease theconcentration of TAA.The concentration of TAA in stem was significant in WN cultivar(F=6040,df=2.9,P<0.022,R=0.757)but not in WA cultivar(F=2,602,df=2.9,P>0.128,R=0.605).WN cultivar is the best adapted to climaticconditions in the region,due to its capacity to store an important reserve of nitrogen compounds. 展开更多
关键词 Vegetative Reserves environmental factors Carya illinoinensis N Cycle
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Quantitative Research on Environmental Risk Factors in Green Bond Pricing
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作者 Ruiwen Wang 《Proceedings of Business and Economic Studies》 2025年第4期374-380,共7页
Amid the global shift toward climate governance and low-carbon transformation,accurately quantifying environmental risk factors within green bond pricing mechanisms has emerged as a critical issue.Drawing on data from... Amid the global shift toward climate governance and low-carbon transformation,accurately quantifying environmental risk factors within green bond pricing mechanisms has emerged as a critical issue.Drawing on data from China’s green bond market between 2018 and 2023,this study develops a multifactor pricing model that integrates environmental risk premiums.Through regression analysis,it empirically investigates the effects of environmental reputation,transparency of information disclosure,and third-party certification on bond risk premiums.The results indicate that green-labeled bonds carry,on average,a 42.6 basis point lower risk premium compared to non-green bonds,while third-party certification further reduces this premium by an additional 54.1 basis points.Moreover,a one standard deviation improvement in the quality of environmental information disclosure leads to a reduction in bond financing costs by approximately 18 to 25 basis points.Issuers operating in high-energy-consuming industries bear significantly higher environmental risk premiums relative to those in low-energy-consuming sectors.By integrating an ESG scoring framework into bond pricing,this study reveals the transmission channels of environmental risks into market pricing and provides a theoretical foundation for enhancing pricing benchmarks in the green bond market. 展开更多
关键词 Green bonds environmental risk factors Pricing model ESG scoring
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Impacts of Environmental Factors on the Structure Characteristics of Avian Community in Shanghai Woodlots in Spring 被引量:32
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作者 葛振鸣 王天厚 +2 位作者 施文彧 周立晨 薛文杰 《Zoological Research》 CAS CSCD 北大核心 2005年第1期17-24,共8页
From March to May, 2004, we selected 8 typical parks or green lands in Shanghai downtown as the study sites to conduct a ornithological research. During this study, total 55 species of birds were recorded, which inclu... From March to May, 2004, we selected 8 typical parks or green lands in Shanghai downtown as the study sites to conduct a ornithological research. During this study, total 55 species of birds were recorded, which included 31 resident and 24 migratory species. With statistics methodology, we analyzed the avian communities with 10 major environmental factors covering the park area, water percentage, vegetation species, canopy cover, shrub cover, grass cover, hill number, location condition, human quantity, path width, the study results indicated that: (1) the following 7 environmental factors were important to impact the structures of the avian community, they were park area, vegetation species, shrub coverage, grass coverage, hill number, location condition of the parks and path width; (2) the avian community of theses urban parks tended to deteriorate in the bird number and diversity; the man-made lake which was currently promoted in the park designing and planning process would not be good to attract the birds. 展开更多
关键词 Urban avian community Bird diversity Key environmental factor Shanghai park
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The Effect of the Novel "light fertilizer" on the Environment Factor in High Tunnel and Growth of Brassica Chinensis 被引量:7
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作者 李文秀 周宁琳 +5 位作者 陈园园 王佳 朱晓玲 王振江 徐磊 冯伟民 《Agricultural Science & Technology》 CAS 2014年第12期2245-2248,共4页
[Objective] The aim was to study the properties of novel "light fertilizer", photo-conversion film, in order to evaluate its effect on the environmental factors and morphogenetic process of crops in the high tunnel.... [Objective] The aim was to study the properties of novel "light fertilizer", photo-conversion film, in order to evaluate its effect on the environmental factors and morphogenetic process of crops in the high tunnel. [Method] Photo-conversion film and Iongevous anti-dropping film were compared in terms of light, air and soil temperature utilizing the Facilities of leafy agriculture high tunnel intelligent monitoring system. Verifying the results by farmland experiment. [Result] Photo- conversion film indeed improved the light quality of high tunnel compared with the Iongevous anti- dripping film. The air and soil temperature was raised several degrees. Results of farmland experiment show that the average value of brassica chinensis fresh weight increased 19.15% compared to the control. [Conclusion] Photo-conversion film promotes more crop growth than Iongevous anti-dropping film due to improvement of light quality, air and soil temperature. 展开更多
关键词 Photo-conversion film environmental factors Light quality WARMING Light quality Yield increase Brassica chinensis
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Grey Relational Analysis between Chlorophyll a and Environmental Factors in ShaHu Lake 被引量:5
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作者 邱小琮 赵红雪 孙晓雪 《Agricultural Science & Technology》 CAS 2010年第7期80-82,共3页
[Objective] The aim was to explore effects of environmental factors on the content of Chlorophyll a in ShaHu Lake.[Method] Based on the data in Shahu Lake from November in 2007 to September in 2008,the relationship be... [Objective] The aim was to explore effects of environmental factors on the content of Chlorophyll a in ShaHu Lake.[Method] Based on the data in Shahu Lake from November in 2007 to September in 2008,the relationship between chlorophyll a and environmental factors like water temperature,pH,secchi-depth (SD),total nitrogen,total phosphorus and potassium permanganate index was studied by grey relational analysis method.[Result] The main environmental factors affecting the content of Chlorophyll a in ShaHu Lake were in order of water temperature potassium permanganate index 〉total nitrogen 〉pH〉 total phosphorus 〉SD.[Conclusion] The research provides reference for the control of eutrophication and the reasonable development and utilization of Shahu Lake. 展开更多
关键词 Shahu Lake Chlorophyll a environmental factors Grey relational analysis
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Inducible Expression of Translation Elongation Factor 1A Gene in Rice Seedlings in Response to Environmental Stresses 被引量:14
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作者 李子银 陈受宜 《Acta Botanica Sinica》 CSCD 1999年第8期800-806,共7页
Differences of gene expression between salinity_stressed and control rice ( Oryza sativa L. ssp. indica ) cultivar “Zhaiyeqing 8' were compared using differential display PCR (DD_PCR) technique. Sequence an... Differences of gene expression between salinity_stressed and control rice ( Oryza sativa L. ssp. indica ) cultivar “Zhaiyeqing 8' were compared using differential display PCR (DD_PCR) technique. Sequence analysis of one salt_inducible cDNA clone revealed that this clone represented a new member of rice translation elongation factor 1A (eEF1A) gene family and was tentatively named REF1A. Northern blot hybridization using REF1A fragment as a probe was performed to investigate the expression of rice translation elongation factor 1A gene in response to various environmental factors. It was observed that expression of the eEF1A gene in rice shoots was dramatically induced by salinity stress or exogenous application of abscisic acid (ABA). The induction of this gene by ABA stress occurred more quickly than that by salinity stress. In addition, expression of rice translation elongation factor 1A gene was also induced by drought (15% PEG6000), cold (4 ℃) or heat_shock (37 ℃) stresses. The results suggested that the induction of translation elongation factor 1A gene expression by environmental stresses might reflect the general adaptive response of rice plants to the adverse circumstances. 展开更多
关键词 RICE Differential display PCR Translation elongation factor 1A environmental factors Differential expression
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Relationship between Phytoplankton Distribution and Environmental Factors in the Chukchi Sea 被引量:3
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作者 林更铭 杨清良 唐森铭 《Marine Science Bulletin》 CAS 2009年第2期55-64,共10页
Based on the samples collected from the Chukchi Sea during the FCNARE cruise from July to August in 1999 with the "Xuelong", the research vessel of SOA, China, the relationship between the distribution characterizat... Based on the samples collected from the Chukchi Sea during the FCNARE cruise from July to August in 1999 with the "Xuelong", the research vessel of SOA, China, the relationship between the distribution characterization of phytoplankton and environmental factors was analyzed with Primer 5.2 software. The result showed that the assemblages of phytoplankton in Chukchi Sea can be divided into three ecological groups: Arctic-boreal group, distributed mostly in northeastern ice-edge where the depth is more than 2 000 m and affected directly by Arctic Ocean; Boreal group, distributed in shelf-break ice in the center water where the depth is less 100 m; Eurythermal group, mainly distributed in the south which exchanged with North Pacific water through Bering Strait. The species diversity, cell density and distribution variability of phytoplankton among stations were great different. The range of phytoplankton density among stations was 1.6 × 10^3- 90 680.2 × 10^4 cells/m^3, and the ranges of diversity index and evenness index among stations were 0.07 - 0.87 and 0.33 - 3.82, respectively. Principal components analysis (PCA) showed that temperature and salinity had made important roles in the distribution of phytoplankton in the Chukchi Sea. Furthermore, the different influences of the variant water regimes, and the extremely dynamic physical nature of the drifting pack ice (e.g. packing, breaking up and melting ) introduce short-term variability into the water conditions that no doubt affect the phytoplankton distrubition. 展开更多
关键词 Chukchi Sea Phytoplankton Distribution environmental factors Multivariate analysis
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Effects of Environmental Factors on NH_4^+ Release in Sediment from Chaohu Lake 被引量:3
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作者 刘静静 汪家权 徐文炘 《Agricultural Science & Technology》 CAS 2008年第3期153-156,共4页
[Objective] The aim of the research was to reveal the influence mechanism of sediment-water exchange of nutrients in Chaohu Lake. [Method] The effects of environmental factors (overlying water, temperature, pH and dis... [Objective] The aim of the research was to reveal the influence mechanism of sediment-water exchange of nutrients in Chaohu Lake. [Method] The effects of environmental factors (overlying water, temperature, pH and dissolved oxygen concentration) on NH_4^+ release in sediment from Chaohu Lake were studied under controlled laboratory conditions. [Results] With the rising of temperature and the decrease of NH_4^+ concentration in overlying water, NH_4^+ released from sediment increased significantly. pH had a great effect on NH_4^+ release with a complicated mechanism. The largest release amount of NH_4^+ under anaerobic condition was about 6 times as much as that under aerobic condition. [Conclusion] This research would provide theoretical support for environmental management of Chaohu Lake in the project of leading water from the Yangtze River to Chaohu Lake. 展开更多
关键词 NH_4^+ release environmental factors SEDIMENT Chaohu Lake
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Research on the Relationship between Three Isomers of Microcystins and Environmental Factors 被引量:3
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作者 张洪玲 蔡金傍 李文奇 《Agricultural Science & Technology》 CAS 2011年第9期1342-1346,共5页
[Objective] The relationship between three isomers of microcystins and environmental factors were studied in the fields.[Method] Three isomers of microcystins (MC-LR,RR and YR) from water of five sampling spots in a... [Objective] The relationship between three isomers of microcystins and environmental factors were studied in the fields.[Method] Three isomers of microcystins (MC-LR,RR and YR) from water of five sampling spots in a northern reservoir were observed for one year with High Performance Liquid Chromatography analytical method in order to study the relationship between three isomers and environmental factors.[Result] The three isomers of microcystins showed positive correlation with chlorophyll a;LR and YR isomers all had significant linear positive correlations with the water temperature,but the RR isomer showed no significant correlation with the water temperature;LR and YR isomers had relatively significantly correlativities with the contents of total nitrogen,nitrate nitrogen and organic nitrogen,while the RR isomer only showed a significant negative correlation with the content of nitrate nitrogen;LR and RR isomers both showed significant positive correlations with the contents of total phosphorus and organic phosphorus,while the phosphorus hardly affected the YR isomer and showed no evident correlation.[Conclusion] The relationship between three isomers of microcystins and environmental factors such as chlorophyll a,water temperature,nitrogen,phosphorus were studied and investigated the reasons,which might offered a reference for controlling the growth of blue algae in water and toxin synthesis. 展开更多
关键词 RESERVOIR MICROCYSTINS ISOMERS environmental factors
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Effects of Environmental Factors on Tomato Growth 被引量:3
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作者 武利明 张喜春 肖光辉 《Agricultural Science & Technology》 CAS 2015年第2期272-277,共6页
[Objective] This study was conducted to evaluate the effects of environmental factors on the biological characteristics of tomatoes.[Method] The growth traits such as plant height,stem diameter,leaf shape index of tom... [Objective] This study was conducted to evaluate the effects of environmental factors on the biological characteristics of tomatoes.[Method] The growth traits such as plant height,stem diameter,leaf shape index of tomato plants grown under different environmental conditions(temperature,light and soil moisture content)were measured and compared.[Result] The effect of light on tomatoes was higher than that of soil moisture in high-temperature environment(30 ℃ or higher);while the speed of tomato plant growth and fruit development were improved by low light.The synthesis of chlorophyll was influenced by soil moisture and light,and greater impact of soil water content on the synthesis of chlorophyll was observed.Among the three treatments,the chlorophyll content of all the three tomato cultivars was in a descending order as follows:control〉 shading treatment〉 drought treatment.[Conclusion] This study will provide references for the control of temperature,light and soil water in tomato cultivation. 展开更多
关键词 Tomatoes environmental factors Growth and development
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Correlation Between the Animal Community Structure and Environmental Factors in Dongbei Cave and Shuijiang Cave of Guizhou Province 被引量:10
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作者 黎道洪 《Zoological Research》 CAS CSCD 北大核心 2006年第5期481-488,共8页
Mollusks, arthropods and chordates which were visible to the naked eye were observed and collected in Dongbei and Shuijiang caves of Libo county five times between February and July from 2002 to 2005. Four hundred and... Mollusks, arthropods and chordates which were visible to the naked eye were observed and collected in Dongbei and Shuijiang caves of Libo county five times between February and July from 2002 to 2005. Four hundred and forty samples from Dongbei Cave were classified into three phyla, five classes, 10 orders, 20 families and 39 species or groups of species. Four hundred and ninety-eight samples from Shuijiang Cave were classified into three phyla, six classes, 11 orders, 20 families and 25 species or groups of species. Six animal communities were identified in the light belt of the two caves according to their species types and numbers of individuals in the light belt of two cave. The communities which have the highest values of species richness community diversity, maximum diversity, evenness, dominance and community similarity are respectively: B (4. 1059), H (2.4716), B (3.3322), E (0.9042), C (0.3442) and A - C (0. 5251). The community diversity and correlation of environmental factors were also studied. The temperature, humidity, content of CO2 and N2, content of organic matter and some inorganic salts in soil were analyzed by Pearson correlation. The results showed that the content of organic matter in soil is positively related to species number, species richness and maximum community diversity, with correlations of 0. 885, 0.909, 0. 868 respectively (two-tailed significance test, P ≤ 0. 05), and significantly positively related to diversity, with the coefficient of 0.611, (two-tailed significance test, P ≤ 0. 1). This suggests that the content of organic matter in soil is one of the important elements influencing the community variation of cave animals. Outside the cave, temperature and humidity are important factors impacting on community diver- sity. As the temperature in all seasons in the cave is stable and the humidity is always high (above 90% ), the temperature and humidity have weak correlation to community diversity in caves. 展开更多
关键词 Animal community structure environmental factor Dongbei Cave Shuijiang Cave Guizhou province
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Analysis on the Influencing Factors of Residents' WTP for Environmental Protection in Tourist Destination——A Case Study of Yellow River Stone Forest in Jingtai of Gusu Province 被引量:1
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作者 王蕾 魏宝祥 《Journal of Landscape Research》 2010年第7期84-88,共5页
On the basis of questionnaire survey,by adopting Contingent Valuation Method,residents' WTP for the protection of Yellow River Hoodoo National Geopark in Longwan Village,Jingtai County of Gansu Province was invest... On the basis of questionnaire survey,by adopting Contingent Valuation Method,residents' WTP for the protection of Yellow River Hoodoo National Geopark in Longwan Village,Jingtai County of Gansu Province was investigated.The result showed that tourism development had greatly influenced local society,economy and culture.Residents in this area had a strong awareness of all the factors above mentioned and showed a positive attitude.Local residents would definitely like to provide a certain degree of labor or money to promote the development of tourism,which was different from the residents' attitude of developed countries.To some extent,it reflected the characteristics of tourism development in developing countries.However,the result of this paper that demographic among residents had little effect on WTP also differed from previous researches.The improvement of living standard and residents' consciousness of environmental protection were the main reasons affecting residents' WTP.Besides,the amount of payment was also in remarkable correlation with the improvement of living standard and the destruction degree of local ecological environment. 展开更多
关键词 WILLINGNESS to Pay(WTP) Influencing factors environmental CONSCIOUSNESS Yellow River Hoodoo National GEOPARK
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Plankton community composition in the Three Gorges Reservoir Region revealed by PCR-DGGE and its relationships with environmental factors 被引量:27
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作者 YAN Qingyun YU Yuhe +2 位作者 FENG Weisong YU Zhigang CHEN Hongtao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第6期732-738,共7页
To explore the relationships between community composition and the environment in a reservoir ecosystem, plankton communities from the Three Gorges Reservoir Region were studied by PCR-denaturing gradient gel electrop... To explore the relationships between community composition and the environment in a reservoir ecosystem, plankton communities from the Three Gorges Reservoir Region were studied by PCR-denaturing gradient gel electrophoresis fingerprinting. Bacterial and eukaryotic operational taxonomic units (OTUs), generated by DGGE analysis of the PCR-amplified 16S and 18S rRNA genes, were used as surrogates for the dominant "biodiversity units". OTU composition among the sites was heterogeneous; 46.7% of the total bacterial OTUs (45) and 64.1% of the eukaryotic OTUs (39) were identified in less than half of the sampling sites. Unweighted pair group method with arithmetic averages (UPGMA) clustering of the OTUs suggested that the plankton communities in the Xiangxi Rive sites were not always significantly different from those from the Yangtze River sites, despite clear differences in their environmental characterizations. Canonical correspondence analysis (CCA) was applied to further investigate the relationships between OTU composition and the environmental factors. The first two CCA ordination axes suggested that the bacterial community composition was primarily correlated with the variables of NO3^--N, dissolved oxygen (DO), and SiO3^2--Si, whereas, the eukaryotic community was mainly correlated with the concentrations of DO, PO4^3--P, and SiO3^2--Si. 展开更多
关键词 plankton community environmental factors denaturing gradient gel electrophoresis (DGGE) spatial pattern Three Gorges Reservoir Region
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